Caster.



R.W. MlLLARD.

EASTER.

APPLICATION man OCT. 1a, 1916.

L230,502. Patented June 19, 1917.

WITNESSES INVENTOR y %%%M MW ATTORNEYS UNITE STATES PATENT OFFICE:

REGINALD W. MILLARD, 0F MERIDEN. CONNECTICUT, ASSIGNOR TO FCSTER,MERRIAM & COMPANY, or MERIDEN, CONNECTICUT, A

CORPORATION OF CONNECTICUT.

CASTER.

Specification of Letters Patent.

Patented June 19, 1917.

Application filed October 18, 1916. Serial N 0; 126,408.

specification.

This invention relates generally to casters, and has more particularreference to metallic sockets for caster-shanks. When casters aredesigned to be employed in connection with comparatively light-weightarticles of furniture, such as chairs, small tables, stands and thelike, a longitudinal bore is provided at the end of the leg of thearticle and the caster-shank is frequently directly inserted therein,but'in connection with heavier articles, such as pianos, large tables,side-boards and the like, or articles which are designed to sustain aheavy load, such as large bookcases, lounges or settees, and the like,it will be apparent, first, that the wooden socket for thecaster-shank-should be reinforced, to prevent splitting of the woodunder the lateral strains created when the heavy article is moved, and,second, that greater freedom of movement of the roller in a lateraldirection, to follow the direction of movement of the article itself, isrequired than can be obtained in any practical manner when thecaster-shank is either firmly or loosely directly embedded in the wood.I

Therefore, metallic sockets of substantially tubular form have beenprovided, these sockets being designed to be firmly embedded in thebores provided therefor at the ends of the legs or in thelower face ofthe body portion of the article, these metallic sockets receiving andretaining the castershank which is usually rotatable therein.

These sockets have heretoforebeen provided either in the form ofcastings or in the form of sheet-metal stampings. Castings areobjectionable for this purpose for many well-known reasons, amongwhichare that of excessive size and weight and that of the brittleness of.cast-metal. 7 While a stamped sheet-metal socket is undoubtedly amaterial improvement over acast socket, dilficulty has been experiencedin economically forming the same from a fiat blank in such manner as todependably fulfil the requirementswhich are, among others, that tiallyof being firmly and rigidly held in place when inserted in the boreprovided therefor, and that of providing a bearing for the caster-shankwhich, while the latter is freely rotatable therein, will so snugly fitthe same as to prevent appreciable lateral movement, or vlbrationor'oscillation thereof.

The principal objects of the present inventlon are the provision of astamped sheet- -metal socket which may be readily formed at oneoperation from a suitable blank, which when formed maybe readilyinserted in the bore provided therefor in the article to be supported,which is self-securedat least to the extent of relieving strains uponother, fastening means-against dislodgment when positioned in said bore,and which provides the desired bearing for the caster-shank which, inthe case of exceedingly heavy articles, such as pianos, is preferablypermanently mounted in said socket yet freely rotatable therein.

y invention will be more readily understood by reference to theaccompanying drawings, forming a part of this specification, in whichFigure 1 is aside elevation of a caster mounted in a socket embodying myinvention;

Fig. 2 is a front be) view thereof; 7

Fig. 3 is a central section, taken substan- (or rear, as the case may onthe line 33 of Fig. 2, including,

a fragment of a leg of the articlewhich the caster is designed tosupport, and

Fig. lis a-plan view of the blank from which the preferred form ofsocketis stamped.

Referring now to the drawingsin detail,

numeral 7 designates the cylindrical shank of a caster, preferablyprovided with a substantially dome-shaped end 8 and having an annulargroove or channel 9 "near the end I thereof. This shank has preferablyrotative connection with the yoke 10, the arms of which carry the axle11 upon which the roller 12 is mounted. Theabove merely describes inbrief a common construction. a V

A metallic socket 13, embodying my.in vention, is designed to be stampedat one operation from a flat sheet-metal blank, and

and well-known I I have shown in Fig. 4: the configuration or I contourof a blank which, as at present advised, best serves my purpose. As willbe seen, this blank comprises a strip of metal having relatively wideand substantially rectangular end portions 1 1 and 15, bridged orconnected by a relatively narrower portion 16 which gradually tapersfrom its ends toward the middle thereof, and at the middle andrelatiyely narrowest portion of the strip are provided the laterallyprojecting, elongated, oppositely-disposed tongues 17 and 18. Thesevarious strip-portions are so proportioned that when the strip is bentat the middle thereof and the opposite ends brought contiguous to eachother, the blank being simultaneously imparted a cylindrical form, theopposite recesses 19 and 20 (Figs. 1 and 2) formed at each side of therelatively narrow strip-portion 16 will be of substantially the samecontour and approximately of the same size as the tongues 17 and 18which, having also been simultaneously curved to cylindrical form, butin a transverse direction, are bent over into said recesses, which theyfall a trifle short of filling, as shown in Figs. 1 and 2, although thewhole structure is now substantially in the form of a butted tube with aclosed, and preferably dome-shaped, end.

The fiat blank is obviously of such size that the tube formed therefromwill snugly fit the bore 21 in the leg or other portion 22 of thearticle to be supported. It has been the general practice to firmlysecure the socket within the bore by means of a plate 23 engaging saidsocket through the edges of a central orifice in said plate pressedbetween shoulders formed by an annular groove or channel at the end ofthe socket, said plate being secured to the bottom of the leg or otherportion of the article to be carried preferably by means of screws 2%2 1. However, on account of the shocks and jars to which both caster andsocket are subjected when a heavy article carried thereby is being movedfrom one place to another. these screws have a tendency to work loose,and it will be apparent that my improved socket is so constructed andmounted as to relieve, to a more or less great extent, the strains uponthe screws. In the first place, the in herent resiliency of sheet-metalprevents its remainingunless its elastic limit has been passed-in theform to which it may have been bent. the elastic forces invariably returning the bent portions for at least a slight distance in a reversedirection. T herefore, my socket is not in true cylindrical form priorto insertion in the bore, and when therein the tendency of the sidewalls to expand at the lower portions thereof causes the socket.substantially as a whole, to more firmly grip the wood in which it isseated.

These elastic forces are even more marked in the bent tongues 17 and 18which. being shorter, are relatively stifler, and these expanding forcescause the ends of the tongues to bite into the wood as shown-possibly toa somewhat exaggerated degree for purposes of illustration in Fig. 3,and thus firmly resist downward movement of the socket in its seat underany ordinary forces tending to dislodge the former.

Near the end of each of the tongues 17 and 18 is provided a smalldepression or indention 25, forming an interior protuberance whichprojects into the groove or channel 9 in the shank 7 of the caster, thussnugly and firmly retaining said shank in said socket yet permitting ofrotation of the former. It will be noted, furthermore, that the grooveor channel at the bottom of the socket, in which the plate 21 ismount-ed, also provides a lower bearing for the castershank.

It is believed to be apparent from the foregoing that I have provided ametallic socket for a caster-shank which is simple in construction,inexpensive in cost of manufacture and possessing a high degree ofstrength, and one which is so firmly seated when in place as toeliminate the necessity for the provision of a retaining plate, ifdesired, and which has all of the desired characteristics and performsall of the desired functions which a device of this character shouldhave or is ordinarily called upon to perform.

Many modifications 'of minor details of my improved metallic socket forcastershanks will doubtless readily suggest themselves to those skilledin the art to which it appertains, and I therefore do not desire tolimit my invention to the specific construction herein shown anddescribed.

I claim as new and desire to secure by Letters Patent:

1. A socket for casters comprising a sheetmetal body of substantiallyuniform cylindrical configuration throughout its entire length andhaving downwardly directed tongues substantially forming parts of thecylindrical side wall thereof, and means on said tongues adapted to.cooperate with complemental means on the caster-stem to be inserted insaid socket to retain said stem in said. socket.

A socket for casters comprising an integral, tubular, sheet-metal bodyof substantially uniform diameter throughout the length thereof andhaving downwardly directed, oppositely located tongues substantiallyforming parts of the cylindrical wall of the tube, and exteriorindentions in said tongues forming interior lugs adapted to project intoan annular channel in the easter-stem to be inserted in said socket.

3. As a socket for casters, a hollow body comprising an integralsheet-metal blank shaped to provide a butted tube of substantiallyuniform diameter having a rounded upper end and an open lower end, andtongues depending from the base of the 5 rounded portion of said upperend and prowall and the free ends of said tongues projecting slightlyoutwardly therefrom.

In testimony whereof I aflix my signature.

REGINALD W. MILLARD.

jecting into corresponding recesses in the Witnesses: tubular wall ofsaid body, the bases of said J. B. COGGINS, tongues being flush with thesurface of said H. R. CHALKER.

flovies of this patent may be obtained for five cents each, byaddressing the "Commissioner of Patents,

I no Washington, D. c.

